1. Field of the Invention
The present invention generally relates to a broadcast receiving system, and more particularly to a broadcast receiving system which receives two or more signals of different frequency bands.
2. Description of the Related Art
In recent years, with the spreading of information processing systems, such as personal computers, the implementation of information processing systems to receiving various kinds of broadcasts including FM broadcasting is performed. However, the information processing systems originally are not produced for reproducing the audio signals, they have the problem in that the quality of the audio signals outputted is degraded.
In order to overcome the problem, the method is proposed in which the broadcast signal received by the information processing system is converted into a signal of a predetermined high frequency, the resulting high-frequency signal is transmitted to an audio system, such as “mini-compo”, and the high-frequency signal received by the audio system is converted again into the broadcast signal with the original frequency so that the demodulation of the broadcast signal is performed.
Such a method is known from, for example, Japanese Laid-Open Patent Application No. 2002-044776.
FIG. 9 shows the composition of a conventional broadcast receiving system.
As shown in FIG. 9, the broadcast receiving system 500 is provided for receiving the FM broadcast signal, and this system is incorporated in an audio system. The broadcast receiving system 500 is equipped with the antenna 502, the FM tuner 504, the antenna 506, the frequency converter 508, and the FM tuner 510.
The antenna 502 receives the FM broadcast signal and outputs it to the FM tuner 504. The FM tuner 504 demodulates the FM broadcast signal and outputs the audio signal.
On the other hand, when the information processing system converts a broadcast signal received by itself into a signal of a predetermined high frequency and transmits again the high frequency signal, the antenna 506 receives the high frequency signal concerned, and outputs it to the frequency converter 508.
The frequency converter 508 converts the received high frequency signal into the signal of the FM frequency band, and outputs it to the FM tuner 510. The FM tuner 510 demodulates the signal of the FM frequency band output from the frequency converter 508, and outputs the audio signal.
However, the conventional broadcast receiving system 500 requires both the tuner 504 which demodulates the directly received broadcast signal and the tuner 510 which demodulates the signal that is acquired by carrying out the frequency conversion of the high frequency signal transmitted by the information processing system. It is difficult for the conventional broadcast receiving system to provide the miniaturization of the device and the cost reduction because of the use of the multiple tuners.